Fluid-actuated well packer



Nov. 8, 1966 G. H. TAUSCH 3,283,820

FLUID-ACTUATED WELL PACKER Filed Feb. 13, 1964 3 Sheets-Sheet 5 BY 2 C M ATTO/FA/iy United States Patent 3,283,820 FLUID-ACTUATED WELL PACKER Gilbert H. Tausch, Houston, Tex., assignor to Cameo, Incorporated, Houston, Tex., a corporation of Texas Filed Feb. 13, 1964, Ser. No. 344,678 Claims. (Cl. 166-420) This invention relates to subsurface well equipment and more particularly to an improved assembly for packing Off of annulus space surrounding a pipe which extends through a well bore. Conventional packer assemblies involve a deformable collar sleeved on a tubing string mandrel to be lowered through the well to a selected depth whereupon the collar is radially expanded into close fitment with a well bore liner casing and is so held by slip elements carried by the mandrel and wedged outwardly into clutching engagement with the casing.

It is an object of the present invention to provide an improved packer assembly whose deformable collar can be set in expanded packing relationship in response to differential fluid pressures applied on a slidable piston cylinder and directed thereto on opposite sides of the cylinder enclosed piston fixedly secured relative to the mandrel.

Another object of the invention is to provide a packer unit having a full open bore through the packer mandrel for the free passage through and below the packer of any of various well-working tools, including a packer-setting tool, and which packer unit can be incorporated either singly or in multiples, as a group of vertically spaced apart units to be set in any desired selective order.

A further object of the invention is to provide a packer unit for cooperative reception therein of a setting tool which effects evacuation of fluid from one variable volume chamber Within the slidable cylinder and on one side of the fixed piston and enables either or both a hydrostatic or a pumped fluid column to act on the cylinder within the variable volume chamber on the opposite side of the fixed piston.

Other objects and advantages will become apparent upon inspection of the accompanying drawings wherein FIGS. 1A and 1B are companion views, partly in elevation and partly in vertical section, illustrating one embodiment of the invention; FIGS. 2 and 3 are somewhat schematic simplified views in vertical section of the packer assembly and respectively illustrating the assembly just before and just after a packer expansion operation, and FIGS. 4A and 4B are companion views, in part elevation and part vertical section, of another preferred embodiment of the in- V venti-on.

The packer assembly as illustrated in FIGS. 1A and 1B includes an inner elongate tubular member 1 having coupling connections at opposite ends for connection in and as .a part of a sectional string of tubing for production of The internal diameter of the tubular member or mandrel 1 conforms to the bore size of the string as a whole and accommodates the free passage of wire line and other working tools. Conveniently, the mandrel 1 consists of a number of separate tubular parts joined in end-to-end succession, such as an upper coupling section 2, an intermediate tubular section 3, a latch keeper section 4, and a bottom section 5. The bottom of the lower section 5 may have a screw-threaded pin end for coupling connection within a collar 6 while the uppermost mandrel sect-ion 2 terminates in a box end for receiving the threaded pin of a next succeeding tubing string section.

Located within an internal annular groove in the section 2 is a stack of rings or bands, including a pair of axially spaced apart magnet-carrying rings 77 and cooperating spacer rings 8-8. Each magnet-carrying ring 7 is provided with two annular rows of permanent magnets in the form of discs 9 projecting through the rings. All the 3,283,820 Patented Nov. 8, 1966 "ice magnets of one row will be positioned with their north poles facing inwardly while the magnets in the companion row will have their south poles facing inwardly and the carrying rings will be of nonmagnetic material with the result that an inwardly-protruding magnetic field will extend into the mandrel bore at each of the magnet-carrying rings. The fields will signal and affect actuation of a packer-setting tool as later will be described. By the use of interchangeable spacer rings 8-8, the magnetcarrying rings 77 can be variously spaced apart selectively as when a number of packer units are incorporated in the same tubing string so that the space relationship of the magnetic fields will differ in each packer unit. Thus the magneto devices of the setting tool can have a spaced apart relationship to match or be coded to any selected field spacing, and the packer assemblies of .a group can be set or actuated in any given order.

Immediately below the box end of the coupling section 2, the tubing mandrel 3 is surrounded by a packing mandrel or elongated sleeve 10 which extends downwardly through an upper slip retainer 11, a wedge or expander retainer 12, a packing collar 13 of rubber or other elastic deformable material, a lower slip expander 14, and a lower slip retainer 15. The packer mandrel It) is slidably sleeved on the tubing string mandrel 3 and the slide bearing near their upper ends is sealed as by means of O-rings as shown at 16 in FIG. 1A. An upper terminal band 17 on the packer mandrel has an internal counterbore to pocket a deformable wiper 18, such as molded polytetrafluoroethylene, in stop bearing engagement with the underside of the box end of the mandrel section 2.

The band 17 abuts the upper end of the slip retainer 11 which preferably has one or more set screws 20 connecting it with the mandrel 10. A set of segmental slips 21 are hung within the holder 11 for outward radial displacement and carry external upwardly-facing wickets for cooperation with the casing wall 19. The inner surface in the lower portions of the slips 21 are inclined upwardly and inwardly and in converging relation to an upwardly and outwardly inclined annular surface on the mandrel 10, and between these convergent surfaces are located the mating faces of upwardly-tapered slip expanders or wedges 22 mounted within the holder 12. This holder initially is secured to the mandrel as by means of one or more shear pins 23. interposed between the holder 12 and the upper end of the packer collar assembly 13 is a thrust ring 24.

A similar thrust ring 25 is interposed between the bottom end of the packer collar as-sernbly 13 and the expander 14, the latter of which is initially secured by a shear pin 26 to the mandrel 10. An internal downwardly- :facing shoulder 27 of the expander 14 is shown at the bottom of FIG. 1A in vertically spaced relation to a split ring 28 carried in a pheripheral groove of the packing mandrel 10 for cooperating stop engagement during a packer removing operation as later will be described. At a short distance below the external ring 28, the mandrel 10 has internally thereof a downwardly-facing shoulder 29, which is to be picked up upon abutment therewith by an external upwardly-facing shoulder 30 on the inner mandrel section 4 in the operation of removing the packer following its release.

Near its lower end the outer face of the slip expander 14 tapers downwardly and has slide engagement on mating inclined surfaces on the inner faces of a set of bottom slips 31 having downwardly-facing wickers and being adapted for clutching bearing on the casing 19 upon outward expansion in their holder 15. The holder 15 is initially secured as by a shear pin 32 to the bottom of the sleeve mandrel 10. In addition, the holder 15 fits within and forms the upper portion of an outer tubular member or cylinder 33 and forms a header or closure for the chamber space within the cylinder 33. The end closure header afforded by the holder has slide bearing engageend of a piston skirt 37 sleeved on the inner mandrel section 5. O-rings as at 38 are pocketed on the inside of the closure header 36 for sealing the slide surfaces.

Immediately above the closure 36 a one-way clutch connection is provided between the piston skirt and the slide cylinder and, as shown, includes a wedge 39 which may be a set of circular segments or a split ring having downwardly-facing wickers or ratchet teeth to engage the piston skirt 37 and also having an upwardly-tapered outer surface for slide bearing on the conical interior surface of the cylinder extension 35. At its lower end the piston skirt 37 has an annular enlargement or collar 40 which provides a bearing and vlimit stop for the closure 36 and cylinder 33; Initially, the cylinder is fixedly located relative to the piston skirt as by means of a shear pin 41 connecting the lower end closure 36 to the piston skirt 37.

Carried by the piston skirt and preferably formed integrally therewith is an outwardly-extending annular enlargement or piston head 42 on the peripheral surface of which the cylinder 33 has slide bearing. To assist the closely-fitted slide surface in preventing leakage across the piston is an O-ring seal 43 pocketed within an annular groove in the piston head and engageable with the interior surface of the cylinder 33. The piston head and skirt unit is detachably secured to the inner mandrel section 4 as by means of screw threads at 44. Normally, the piston is fixedly located on the inner mandrel section 4 and subdivides the interior of the cylinder into upper and lower variable volume chambers 45 and 46.

Communicating ports at 47 through the piston skirt 37 land the inner mandrel section 4 provide a fluid transfer passage between the lower chamber 46 and an annular interior groove in the mandrel section 4 and opening into the central bore through the packer assembly. The bore also communicates through an internal annular groove and a port 48 in the wall of the mandrel section 4 with the upper chamber 45 and by way of radial clearance between the bottom of the sleeve mandrel 10 and the inner mandrel section 4 for fluid transfer between the bore and the upper chamber. The inner mandrel section 4 is provided interiorly thereof with an annular keeper groove 49 for reception of a latch dog of a packersetting tool. 'The setting tool is shown in FIGS. 1A and 1B as having been inserted in the bore of the packer and at a position at which its actuation will occur.

It will be understood that the setting tool is inserted at the surface and lowered through the bore only after the installation of the tubing string including one or more of the packer assemblies with the parts in the relative positions as previously described.

The setting tool includes a central body 50 having a pair of axially spaced apart peripheral seals 51-51 to be engaged with the interior surface of the inner mandrel 4 above and below the flow transfer port 47 to thereby seal off the port from the open bore of the tubing string when the tool is in operative position. In the region between the seals a lateral passageway 52 is for communication with a central bore in the body 50 which opens through opposite ends of the body, although initially the central bore or passageway is closed by pins 53 and 54 with the pin 53 being supported by a frangible member 55 carried by the body at its lower end. Below the central body, a downwardly-extending tubular member 56, closed at its lower end, houses a chamber which will be sealed by the pin 53 at some selected low pressure relative to downhole pressures. Thus, the

closed depression chamber may be at atmospheric or subatmospheric pressures. The closure pin 54 for the upper end of the passageway is suspended at the bottom of a depressible plunger 57.

The depressible plunger 57 has an annular camming enlangement 58 which on plunger depression will project one or more latch dogs 59 outwardly into the keeper groove 49 and then extend behind the dogs to hold them projected. Depression of the plunger is effected by the .action on the top thereof of the force of expanding gas generated by a combustible powder charge contained within the shell 60 and arranged for electrical ignition. Ignition current is supplied by batteries located within the upper portion 61 of the setting tool and controlled by a pair of series-connected switches actuated by magnetos indicated generally at 62 in axially spaced relation corresponding to the spacing of the magnetic fields afforded by the permanent magnets carried at the top of the packer unit. Adjustment of the spaced relation of the magneto switches is to be made beforehand for matching relation to the known spacing of the magnetic fields in the packer unit to be set.

After the tubing string has been properly located in the well hole and it is desired to set or expand a packer unit,

a setting tool having its magneto switches properly adjusted is then lowered through the bore into operative relation with the packer. Up to this time the upper and lower fluid chambers 45 and 46 within the actuating cylinder have been in free open communication with the tubing string bore and fluid pressures within the chambers are balanced or equal. However, when the tnansfer passage to chamber 46 is bridged by the tool seals and as soon as both magetos 62 concurrently come Within the influence of magnetic fields, the circuit is closed to fire the charge 60 and depress the plunger 57 which simultaneously projects the latch dogs for anchoring the tool hanger and causes the pin 54 to forcibly strike the closure pin 53. The force breaks the frangible pin 55 and allows the closure pin 53 to drop clear of the passageway and into the bottom of the depression chamber within the housing 56. This opens communication to the depression chamber in the tool and from the chamber 46 below the fixed piston for the transfer or evacuation of any fluid within the piston chamber and .a resultant pressure drop. The opposite piston chamber 45 remains open to the tubing string bore and either or both the hydrostatic pressure, if there be an upstanding column of liquid, or the pressure of fluids pumped into the bore at the surface will act within the upper chamber 45 upwardly on the slide cylinder surface exposed within the chamber, as

for example the downwardly-facing end surface of the slip holder 15, Differential pressure action on the cylinder will first break the shear pins 41, 32, 26, and 23, and move the cylinder upwardly with the force being transmitted from the slips 31 to the expander 14 and through the packing collar 13 to the upper expander 22 whose action on the upper set of slips 21 forces the slips out wardly into firm engagement with the casing wall.v Thereupon, movement of the upper abutment for the packing collar will be firmly resisted and the force will squeeze the packing collar axially and cause its radial deformation and expansion into seal-off relation with the casing. When that occurs, further movement of the expander 14 will be firmly resisted so that the lower set of slips 31 move out into tight clutched engagement with the casing, and the packer will be locked in set relation. During the upward movement of the cylinder, the one-way clutch or ratchet element 39 will have been elevated and slid. on the piston skirt 37 and will wedge itself tightly between the piston skirt 37 and the cylinder extension 35 to re sist downward or return movement of the cylinder. Thereafter the setting tool is removed from the Well and the packer will remain in its set position.

If at any subsequent time it is desired to remove the packer from the well, the tubing string is first rotated to unthread the inner mandrel section 4 from the piston head 42 at the threads 44. When completely unthreaded, the tubing string can be lifted, first to take up clearance between the seats 30 and 29 for carrying the sleeve mand-rel upwardly with the tubing string and thereafter to bring the seats 30 and 29 into engagement for suspending the packer parts above the same. Those exterior packer parts, such as the lower slips, the cylinder, and the piston may drop away until the lower ring on the bottom of the piston is picked up by the upper shoulder of the coupling collar 6. During the upward movement of the tubing string, the slips will have been released and the packing collar relieved of axial squeezing force for its retraction.

As previously described, the invention has been embodied in a retrievable packer assembly, but it can also be embodied in a simplified form of drillable packer assembly, such as shown in FIGS. 4A and 4B. In this instance the tubing string mandrel 101 carries the spaced apart magnet rings 107 at its upper end and has the internal latc'h groove 149 to receive the dogs of a setting tool. In given spaced relation below the keeper groove is the port means 147 in the mandrel for fluid transfer between the bore and the lower chamber 146 of the piston cylinder 133. The upper chamber 145 communicates through a ported passageway 148 extended through the wall of the inner mandrel 101 and the upwardly-extending skirt 137 of the piston head 142 confined within the cylinder 133. Sleeved on the piston skirt is a packing collar 113 as well as an upper slip expander 122 and an upper set of slips 121. Below the packer collar is located a slip expander 114 and a set of slip segments 131. Both sets of slip segments are initially retained by frangible rings 160 encircling these slips to maintain them in contracting relation until such time as wedge force is applied to project them outwardly.

Interposed between the lower set of slips 131 and the top of the slida'ble cylinder 133 is a motion-transmitting ring 161 having an upwardly-tapered interior wedging surface for cooperation with the inclined surface on the back of a ratchet element or one-way clutch 139, which will slide upwardly and resist reverse movement after the packer has been set. At its lower end the cylinder 133 has a closure ring 136 in sliding and sealing relation with the inner mandrel 101.

After the drillable packer assembly is lowered with a tubing string to position, a setting tool can be lowered through the bore and fired to evacuate the bottom chamber 146 whereby the differential pressure will raise the cylinder for setting the packer, and it will be held set by the action of the one-way clutch 139. Should it later be desired to remove the tubing string, the tubing string can be rotated within the set packer for bringing an openended leg of a Z-slot 165 in alinement with the holding pin 166 whereupon elevation of the tubing string will pass the mandrel upwardly and out of the set packer. Should it become necessary to thereafter remove the packer, this can be done by drilling out the relatively soft material of which the parts are formed.

What is claimed is:

1. In a well packer assembly, a deformable packing collar, an inner tubular mandrel extending through the collar and providing locating coaction with one end of the deformable collar, an outer tubular cylinder slidably surrounding the inner mandrel and having force transmitting coaction with the other end of the deformable collar, said tubular cylinder having a portion radially spaced from the mandrel for cooperation therewith in providing .an annular piston receiving chamber exteriorly closed at bothend-s, an annular piston fixedly projected laterally from the mandrel and enclosed within the chamber with a slide sealing fit thereto, pressure fluid transfer passages communicating the bore of the mandrel with the chamber above and below the piston, a tool receivable within said bore and provided with a pair of axially spaced apart annular seals for location above and below one of said transfer passages, a depression chamber within the tool having an initially closed side port in the region between said seals and means operable to open said port upon alinement with said one transfer passage for evacuating the chamber on the side of the piston with which said one transfer passage communicates.

2. In a well packer assembly as in claim 1 wherein the other of said transfer passages remain in open communication with the bore above said seals for pressurization of the piston chamber on the opposite side of the piston.

3. In a well packer assembly,

a deformable annular packing collar,

a tubing string mandrel surrounded by the collar,

abutment means located by the mandrel beyond one end of and engageable with the collar,

an annular piston sleeved on and secured to the mandrel beyond the outer end of the collar, said piston comprising a tubular member having :a laterally outwardly projecting head and a dependent skirt sleeved on the mandrel and being secured to the man-drel by a detachable connection which accommodates separation of the mandrel upon relative rotation thereof,

a piston enclosing cylinder slidably surrounding the mandrel and cooperating with the piston to form variable volume chambers on both sides of the piston,

cylinder movement transmitting means engageable with the other end of the collar for controlling collar deformation in response to cylinder movement, said cylinder having top and bottom inwardly projecting members of which the bottom member has sealing slide bearing on said skirt,

a pair of fluid transfer passages communicating the bore of the mandrel with the variable volume chambers respectively,

means arranged for cooperation with said transfer passages and operable for the differential pressurization of said variable volume chambers to effect cylinder movement, and

a one-way clutch device carried by the bottom member for cooperation with the skirt and retention of the cylinder at a packer-setting position to which the cylinder is moved.

4. In a well packer assembly as in claim 3, the firstmentione-d abutment means including a tubular member interposed between the mandrel and the packing collar and projected above and below the collar, an upper slip held by the upper end of the member for relative lateral movement and an upper slip expander movable axially to exp-and the slip upon upward cylinder travel; said cylinder movement transmitting means including a lower slip held by the movable cylinder for relative lateral movement and a lower slip expander between the last-mentioned slip and the packing collar, said mandrel and said tubular member having cooperating pickup shoulders for abutment with one another upon elevation of the man-drel relative to the piston when detached therefrom and for transmitting mandrel elevation to raise the tubular member and thereby release the first-mentioned slip by carrying the slip upwardly away from its expander, and cooperating pickup shoulders on the inner member and on said lower slip expander for abutment with one another subsequent to release of the upper slip and upon continued elevation of the mandrel for transmitting mandrel elevation to raise the lower slip expander and thereby release the lower slip.

5. In a well packer assembly, a tubing string mandrel, a tubular member sleeved on and detachably secured to the mandrel to accommodate separation and removal of the mandrel from the tubular member, a deformable packi-ng collar surrounding an intermediate portion of the tubular member, two sets of slips and slips expander units below said deformable collar and relatively axially movable toward one another in the transmission of axial squeezing force on the deformable collar, one-way clutch means between the tubular member and one of said units for resisting movement of said units away from one another, and force applying means comprising a locating abutment fixed to the tubular member and engaged with one of said units, a slidable cylinder engaged with the other unit and formed with axially spaced apart s-lidable and sealed hearings on the mandrel and on the tubular member for cooperation therewith in enclosing a piston chamber, an annular piston carried by the tubular member and enclosed within said chamber in peripherally sealed and slide bearing on the internal surface of the cylinder and spaced apart port means separately communicating the chamber space on opposite sides of the piston with the bore of the mandrel for transfer through the port means of differential pressure fluid-s and the slide response thereto of said cylinder and a tool receivable within said bore and provided with a pair of axially spaced apart annular seals for location above and below one of said port means, a depression chamber in the tool having an initially closed side port in the region between said seals and means operable to open said port upon alignment with said one spaced port means for evacuating the chamber space on the side of the piston with which said one spaced port means communicates.

References Cited by the Examiner UNITED STATES PATENTS 2,275,935 3/1942 Baker 166120 3,002,561 10/ 1961 Baker et a1 166-120 3,062,291 11/ 1962' Brown 16'6 120 3,180,419 4/1965 C-Ochr-an et al 1'66120 CHARLES E. OCONNELL, Primary Examiner.

J. A. LEPPINK, Assistant Examiner. 

1. IN A WELL PACKER ASSEMBLY, A DEFORMABLE PACKING COLLAR, AN INNER TUBULAR MANDREL EXTENDING THROUGH THE COLLAR AND PROVIDING LOCATING COACTION WITH ONE END OF THE DEFORMABLE COLLAR, AN OUTER TUBULAR CYLINDER SLIDABLY SURROUNDING THE INNER MANDREL AND HAVING FORCE TRANSMITTING COACTION WITH THE OTHER END OF THE DEFORMABLE COLLAR, SAID TUBULAR CYLINDER HAVING A PORTION RADIALLY SPACED FROM THE MANDREL FOR COOPERATION THEREWITH IN PROVIDING AN ANNULAR PISTON RECEIVING CHAMBER EXTERIORLY CLOSED AT BOTH ENDS, AN ANNULAR PISTON FIXEDLY PROJECTED LATERALLY FROM THE MANDREL AND ENCLOSED WITHIN THE CHAMBER WITH A SLIDE SEALING FIT THERETO, PRESSURE FLUID TRANSFER PASSAGES COMMUNICATING THE BORE OF THE MANDREL WITH THE CHAMBER ABOVE AND BELOW THE PISTON, A TOOL RECEIVABLE WITHIN SAID BORE AND PROVIDED WITH A PAIR OF AXIALLY SPACED APART ANNULAR SEALS FOR LOCATION ABOVE SAID BELOW ONE OF SAID TRANSFER PASSAGES, A DEPRESSION CHAMBER WITHIN THE TOOL HAVING AN INITIALLY CLOSED SIDE PORT IN THE REGION BETWEEN SAID SEALS AND MEANS OPERABLE TO OPEN SAID PORT UPON ALINEMENT WITH SAID ONE TRANSFER PASSAGE FOR EVACUATING THE CHAMBER ON THE SIDE OF THE PISTON WITH WHICH SAID ONE TRANSFER PASSAGE COMMUNICATES. 